A Configurable IC to Control, Readout and Calibrate an Array of Biosensors
We present a novel integrated circuit for a biosensing data acquisition chain. The circuit controls and reads out five bimolecular sensors as well as pH and temperature sensors for biosensor calibration. The IC supports both chronoamperometry (CA) and cyclic voltammetry (CV) measurements, which are commonly used in biosensing. Different voltage waveforms are generated to control CV by using a single configurable waveform generator and programmable constant voltage levels are produced to enable CA. To reduce the area and power consumption of the interface electronics, a unified circuit is designed for CV, CA and pH readout. The biosensors produce currents that are converted by a 13.5-bit sigma delta analog to digital converter. The circuit has been designed and realized in 0.18 μm technology. It consumes 711 μW from a 1.8 V supply voltage, making it suitable for remotely powered and implantable applications.